Cells

1. no membrane-bound organelles
2. Simpler cell structure
3. Eg. Bacteria

1. contain membrane-bound organelles
2. Complex cell structure
3. Eg. Animal & Plant

Nota:

• Nucleus, Cytoplasm, Membrane                PROTOPLASM

1. controls vital cell activities
   1. Eg.
      1. Cell division
      2. Cell growth
      3. Cell repair
2. Porous nuclear membrane
3. Chromatin
   1. DNA
   2. Condense (cell division) = Chromosome
4. Nucleolus
   1. plays a part in making proteins
5. Nucleoplasm

1. 70% water content
2. contain organelles
   1. Mitochondria
      1. 2 membrane
      2. Break down food during respiration
         1. Release ENERGY
   2. Endoplasmic reticulum
      1. Rough
         1. produce & transport proteins (ribosomes) to Golgi apparatus
         2. have ribosomes attached
      2. Smooth
         1. Synthesise & transport
            1. lipids & steroid hormones
         2. Detoxification
            1. Converts harmful substances to harmless
         3. No ribosomes attached
   3. Ribosomes
      1. Attached to ribosomes
         1. Exported via vesicles outside cell
      2. Free
         1. For intercellular usage
   4. Golgi apparatus
      1. Modifies substances (synthesised by the ER)
      2. Package substances into vesicles for secretion (outside cell)
   5. Vesciles
      1. Transport substances btw organelles
   6. Vacuole
      1. Storage of substances in cell
      2. Animal
         1. Small
         2. Many
         3. Store water & food
         4. Usually temporary
      3. Plant
         1. One
         2. Large
         3. Central
         4. Store cell sap
            1. Sugars
            2. Mineral salts
            3. Amino acids
         5. Tonoplast
            1. Membrane surrounding vacuole
   7. ONLY IN PLANTS
      1. Chloroplast
         1. Chlorophyll
            1. Photosynthesis
      2. Cell Wall
         1. Fully permeable
         2. Hard & Rigid
         3. Protect cell frm phyical damage
         4. Provides support
         5. Cellulose
   8. Centioles

1. controls substances moving in and out of cell
2. Partially permeable

1. Process
2. Develop special structures
   1. Specific functions

1. Contains haemoglobin
   1. Binds reversibly w oxygen
2. Transport oxygen
3. Lacks nucleus
   1. Free up more space
      1. carry ↑ haemoglobin
4. Biconcave shape
   1. ↑ S.A to V ratio
      1. more oxygen can diffuse into cell
         1. ↑ rate of oxygen entering RBC
5. Elastic
   1. Bell-shape
      1. Squeeze through vessels smaller than itself

1. No cross-walls / partition walls
   1. No obstrction
      1. Water & mineral salts can move through vessels easily
2. No protoplasm
3. Lignin deposits (vessel walls)
   1. Strengthen vessels
      1. prevent it frm collapsing
4. Bundled tgt

1. Narrow, elongated projection
   1. ↑ S.A to V ratio
      1. ↑ rate of diffusion /osmosis